1. Field of the Invention
The invention relates to a method and apparatus for detecting if liquid is present in a gas, and for segregating the liquid from the gas. Specifically, it concerns the method and apparatus for adiabatically expanding the volume of a gas stream and/or reducing the flow of the gas stream until liquid, if present, segregates from the gas stream, and detecting the segregated liquid by collecting and weighing it.
2. Description of the Prior Art
Detection of liquid and its removal from a gas stream is very important, particularly in exothermic chemical reactions such as chlorination, fluorination, etc., where liquid, if present in the gas stream entering the reactor, causes explosions because of the large amount of exothermic heat generated by reaction of the liquid with the reactants. The detection and segregation of liquid in a gas stream is also important in drying and evaporating operations, for if liquid is present in a gas stream used for drying, then the drying operation is prolonged and perfect drying may not occur. Several methods are used to overcome these problems. In one method, extra heat is added to the gas stream to vaporize any liquid present; a method currently employed in chlorination reactions. However, if the heat supply fails, then liquid may be present and disastrous results may follow. In another method, baffles are used to entrain any liquid particles present, as described by C. E. Graham in U.S. Pat. No. 2,290,323, but baffles are not suitable for early detection of the liquid, and furthermore elaborate baffle systems are required when small amounts of liquid occur in a gas stream. In another method, described by Crawford in U.S. Pat No. 2,268,442, gaseous water is chemically absorbed by a solid, such as lithium iodide, to determine the amount present in the gas stream. However, this technique is inapplicable where both gas and liquid particles of the same chemical composition are present, as in vaporized chlorine, for it cannot distinguish between the gas and liquid because the solid absorbs both. These drawbacks are overcome in the present invention which employs a relatively efficient, simple, rapid detection and segregation of the liquid.